Another Thyroid Thread

[Guest OurIndy]

I apologize if there is a thread that covers this already, I couldn't find it readily though!

 

So Piper (4yo SF) and Indiana (5yo CM) just got a free CBC/CHEM through Tufts (one of the only perks of being a vet student ) and Indy's results just came back. Unfortunately his CBC was invalid because there was a clot in the tube, but his CHEM came back all fine except his T4 is .4ug/dL. I'm pretty sure the low end for normal for a greyhound is .5ug/dL so I'm reading his values as low. I know you have to do a full thyroid panel to get a true diagnosis for a hypothyroid greyhound but .4 is a bit alarming to me! That said, Indiana shows NO hypothyroid symptoms. I mean, lethargic...maybe in terms of another breed, but he's a quintessential greyhound. He sleeps all day unless he's running around like a maniac with his squeaky ball or trotting happily on his frequent walks. In terms of other symptoms, he has the fuzziest butt I've ever seen on a Gh, his weight is great and easy to maintain, no shyness (any stranger is greeted with little hops of excitement and helicopter tail), and not mentally dull at all.

 

Anyone had T4 levels that low with no symptoms? Would you be getting a full thyroid panel?

 

Thanks for any thoughts, and sorry for a probable thyroid repost!

[Batmom]

No symptoms, no need to get a panel. T4 in a greyhound can be 0 and totally normal -- there isn't really a low end.

[greyhead]

Your concern is understandable. We had a full panel redone for one of our seniors who IS hypothyroid, because he is older now and because his T4 was .5., and his internist thought he might need a medicine increase. The panel showed his free T4 to be distinctly high, as was his T3. So without any indication of anything at all amiss, I don't think you need a panel either.

[NeylasMom]

to the above. Don't worry about it.

[Guest OurIndy]

Ok sounds good! I guess if it ain't broke don't fix it!

[OwnedBySummer]

My understanding of the T4 result is that the MEDIAN is .5.

[PrairieProf]

Beth had a .4, we did the full panel, she was totally normal for a greyhound. Agree you shouldn't worry.

[turbotaina]

No symptoms, no need to get a panel. T4 in a greyhound can be 0 and totally normal -- there isn't really a low end.

 

Right. Heyokha's T4 came in at .1 and my normal vet (who was not the vet who did the bloodwork) and I both feel there's no need for further testing. This dog is the polar opposite of a hypothyroid dog. My vet said, "Man, could you imagine him on thyroid supplements?!"

[tydyelady]

Opie's T4 was .2, and with supplements , when retested was .5. I started another thread about this a month or so ago, and I will be having him retested, full panel, supplement free, in a few months. He never exhibited any signs either, except for aggression, but that was not aggression, it was me not knowing how to read greyhound body language.

[Guest Energy11]

Both my Curfew and Goldie are on LOW dose thyroid medications. Goldie's per Dr. Jean Dodds, Hemopet, and Curfew's, per my local vet.

 

I recently had bloodwork done on both of the above, and my new vet here, who I REALLY like, and have a good respect for, suggest doubling both, based on a T4 of 0.4 and 0.5. NO Free T4 was done, just routine testing done in a senior panel. I told the vet I would decline doubling or increasing the dosage, as both dogs were doing VERY well, and I didn't see the need. MOST vets see these low numbers, and panic. I agree with some of the others here. Why treat is there are no symptoms?

 

Of course if you DO see any changes, or just want peace of mind, I would suggest a Free T4.

 

Good Luck!

[turbotaina]

....

Of course if you DO see any changes, or just want peace of mind, I would suggest a Free T4.

 

Good Luck!

 

 

For clarification here, a fT4 is not diagnostic, either. You need to see an elevated TSH in order to definitively diagnose hypothyroidism. That can be tested via MSU (though I think some other labs also do the full panel as well, MSU is the gold standard).

[Guest budsmom]

The nice thing about MSU is that if you request it and tell them the breed of dog, they will include an analysis of the results based on the breed norms. This way, even if the vet isn't familiar with greyhound normal, you're sure to get the right answer.

[greyhead]

I'm sorry, I just can't bite my tongue about this. MSU will not diagnose a greyhound as hypothyroid, if their work on Energy11's Goldie is any indication, unless the TSH is elevated and/or there are thyroid antibodies detected, even if the thyroid hormones are so low as to be undetectable. The problem is that TSH is wrong at least 15% of the time -- and nobody is sure why -- and not all hypothyroidism has an autoimmune cause, in which case there won't be antibodies. Personally, if a dog is symptomatic and running that low on thyroid hormones, I'm going to treat him. If the dog is heavily symptomatic, that's reason enough to consider the hypothesis that such low levels of thyroid hormones are not normal for that dog at that time. So fine, get an opinion along with MSU's panel, but be willing to treat your dog as the individual he is. The OP being a vet, I'd assume she could manage that if need be.

[Batmom]

MSU can't diagnose a dog as hypothyroid without supporting labwork because they don't see the dog. They do state-of-the-art labwork and interpret on that basis.

 

The OP is talking about a dog with no symptoms of hypothyroidism or anything else.

 

 

[BootsyCollins]

Just went through this with Bootsy. His t4 is .6 and we did do the TSH test. His TSH is a "tiny bit high," my vet consulted with another vet, whose specialty I can't remember, and the recommendation was that if he is asymptomatic, not to worry and test again in 6 months.

[greyhead]

MSU can't diagnose a dog as hypothyroid without supporting labwork because they don't see the dog. They do state-of-the-art labwork and interpret on that basis.

 

The OP is talking about a dog with no symptoms of hypothyroidism or anything else.

Hi Batmom,

 

First paragraph, very good point. That's also why I hope people will work with their vets and observations of their dogs.

Second paragraph, I know, so I think she's doing the right thing by doing nothing at this time. I only mentioned her specifically at the end of my post because the situation could change in the future. Hopefully, we'd agree that thyroid function doesn't always stay the same through the lifespan for everyone.

[Guest OurIndy]

I'm sorry, I just can't bite my tongue about this. MSU will not diagnose a greyhound as hypothyroid, if their work on Energy11's Goldie is any indication, unless the TSH is elevated and/or there are thyroid antibodies detected, even if the thyroid hormones are so low as to be undetectable. The problem is that TSH is wrong at least 15% of the time -- and nobody is sure why -- and not all hypothyroidism has an autoimmune cause, in which case there won't be antibodies. Personally, if a dog is symptomatic and running that low on thyroid hormones, I'm going to treat him. If the dog is heavily symptomatic, that's reason enough to consider the hypothesis that such low levels of thyroid hormones are not normal for that dog at that time. So fine, get an opinion along with MSU's panel, but be willing to treat your dog as the individual he is. The OP being a vet, I'd assume she could manage that if need be.

 

 

Just to clarify, I'm not a vet, not yet at least! I'm just a lowly first year vet student. And even after I graduate, I'm sure I'll still be posting questions on the Health and Medical board, as everyone here has so much experience and expertise to offer!

 

Thanks to everyone for the information you've given me. I think that the test results are a good heads up for me to make sure I watch Indy for any hypothyroid symptoms. I think since he presents so differently from a typical hypothyroid dog that I'll postpone the TSH and freeT4 for now. Again, thanks!

[greyhead]

Sorry, I spoke in a confusing way. I didn't mean you, OurIndy, when I said, "So fine, get an MSU panel...." I meant greyhound owners in general. All I really meant about you was that as you get closer to being-a-vet and then are a vet, you should feel more confident than a lot of us do about deciding if your animal (any one you may ever have) is well-described by the ranges and norms or not. (I've become infamous, I'm afraid, for arguing kind of forcefully that group norms and ranges, while necessary, don't define health in every single individual all the time. There are such things as individual set points for metabolism, for instance.)

 

Anyhow, Indy sounds like a splendid boy and the picture of health!